1. Field of the Invention
The present invention relates to a construction machine such as a hydraulic shovel, and more particularly to a frame constitution of a traveling body in a construction machine.
2. Description of the Related Art
A conventional hydraulic shovel 100 disclosed in “Crawler-type Vehicle” (Japanese Unexamined Patent Application Publication 2002-178960) comprises a traveling body 101 to enable movement, and a slewing body 102 which is mounted slewably above the traveling body 101, as shown in FIG. 9.
The slewing body 102 comprises a slewing frame 103, and the slewing frame 103 is provided with a body cover 104 accommodating a motor and the like, a cab 105 which defines the operating cabin, a counterweight 106, and so on, for example.
A working device 107 is provided elevatably at the front portion of the slewing body 102.
A truck frame 108 constituting the main body part of the traveling body 101 is, as shown in FIG. 10, constituted by a center frame 109 positioned in the center by means of steel plate welding or the like, and side frames 112 provided on both the left and right sides of the center frame 109 and extending to the front and rear.
Here, the center frame 109 is constituted by a central circular core 110, and leg parts 111 extending in a front/rear direction and a left/right direction from the outer periphery of the circular core 110 to form an overall H shape.
The leg parts 111 are formed as canning structures by an upper plate portion 111A, a lower plate portion 111B, side plate portions 111C which connect the plate portions 111A, 111B in a vertical direction, and so on.
112, 112 are left and right side frames provided on the tip end side of the leg portions 111 of the center frame 109 by welding. The side frames 112 are formed as frame bodies in a substantially reverse C shape extending in a front/rear direction.
Left and right mudguard covers 125, 125 are disposed respectively on the side frames 112, 112 of the truck frame 108.
Note that “Truck Frame for Construction Machine” (Japanese Unexamined Patent Application Publication H9-202261) is disclosed as another known invention in addition to that described above.
The hydraulic shovel 100 described above (see FIG. 9) travels over various types of ground by driving crawler belts 117 disposed on the traveling body 101 to rotate. As a result, earth, mud, and so on are churned up by the crawler belts 117.
Here, as shown in FIGS. 9, 10, the mudguard covers 125, 125 provided in the vicinity of the crawler belts 117, 117 are constituted so as to extend in a horizontal direction, and hence the earth, mud, and so on that are churned up by the crawler belts 117 may accumulate on top of the mudguard covers 125, 125.
In this case, a worker must remove the accumulated earth, mud, and so on, and if the earth, mud, and so on are left to accumulate, they cause running resistance when the hydraulic shovel 100 is operated.
Hence a blade bracket (not shown) on which an earth-removing blade (not shown) is supported so as to swing freely is connected to the front portion of the traveling body 101.
As the blade performs an earth removal operation, various loads such as large loads are applied to the blade bracket which supports the blade. It is therefore desirable that an operating load transmitted to the blade bracket be processed appropriately in order to improve the load-withstanding strength of the vehicle body.